Generally I find it much easier to get the bumper off. In theory it is possible by undoing the fuse box, air trunking etc., but it tends to be a painful exercise, if indeed you ever managed it.
H1 and H7 55w are what you need. I swapped my H7's for the Philips +150% 'Racing Vision', which are a big improvement, better than the Osram 'Night Breaker's I previously used. Edit: See now that the new GT200 version of the Philips 'Racing Vision', claim +200% more light rather than the claimed +150% I now have.
As with all bulbs, buy from an accredited supplier, if you can. More on the net are fake than are real, I think!